Chantix users may be at higher risk of heart attack

UNDATED (CNN) - When smokers take Chantix to help kick the habit, they may face a higher risk of a heart attack or stroke.

That's according to a new study published in the Canadian Medical Association Journal.

Researchers say those who used Chantix had a higher risk of a serious cardiovascular event.

Pfizer makes the drug.

According to the New York Times, Pfizer said the study was too limited to draw conclusions about the risks.

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